This invention relates generally to lighting and guidance systems and particularly to those utilized in flush mounting within the surfaces of roadways, airport runways, sidewalks or other similar surfaces.
For many years, the need for convenience and safety in various human facilities and environments fostered the use of illumination to provide guidance and direction. This need is particularly critical in environments tended to remain poorly illuminated or dark as well as indoor and outdoor environments during evening and night hours. From earliest illumination systems using crude candles and gas lamps through the development of electrical lamps such as incandescent, florescent or neon and the like, the trend has been toward creating illumination apparatus which functions to provide visual direction and guidance for the observer or traveler.
With the advent of vehicular traffic such as automobile, trains and airplanes illuminated direction and guidance systems became a specialized area of activity. The object of such systems became generally focused upon providing a visual direction or guidance benefit rather than general area illumination. Thus, facilities such as airport runways and taxi ways as well as vehicular roads and trackways and railways used by trains have enjoyed increased safety and efficiency through lighted direction and guideway systems.
While the fabrication used in lighted directed guidance systems varies substantially, typically all utilize an elongated array of illumination elements such as lamps or the like supported within a strip shaped housing which is coupled to a convenient source of power. In some units, a solar power apparatus is provided to store energy during day light hours and provide illumination during night time hours. The strip shape may vary from simple elongated straight or curved elements to more complex symbols such as arrowheads or diamonds and may, in some instances, even form words or abbreviations.
With the advent of higher power output light emitting diodes (LED) the capabilities and flexibility lighting strips for use in direction and guidance systems enjoyed a dramatic improvement. Light emitting diodes are substantially more reliable and durable than previously used illumination elements such as incandescent lamps or the like. In addition, the small size and high power output of the newly developed LED""s greatly facilitated the use of lighting strips which may be flush mounted within roadways, airport runways or other areas subject to vehicular traffic.
Not surprisingly, the need for effective lighting strips for direction and guidance systems has prompted practitioner""s in the art to create a variety of lighting strip structures. For example, U.S. Pat. No. 5,927,845 issued to Gustafson et al. sets forth an INTEGRALLY FORMED LINEAR LIGHT STRIP WITH LIGHT EMITTING DIODES having at least one light emitting diode connected between electrical bus elements to provide illumination when the bus elements are electrically activated. An extruded plastic material completely encapsulates the bus elements and the at least one LED. The encapsulating material provides a barrier to protect the elements from damage and render the light strip impervious to moisture. A process for manufacturing the integrally formed single piece light strip using continuously fed bus elements and an extruder is also set forth.
U.S. Pat. No. 4,993,868 issued to Eigenmann sets forth a CONTINUOUS PREFABRICATED ROAD-MARKING TAPE WITH COMPOSITE STRUCTURE AND PASSIVE AND ACTIVE OPTICAL EFFECT COMPLETELY INDEPENDENT FROM OUTSIDE INVESTMENT AND EXTERNAL ENERGY SOURCE includes a continuous horizontal road-marking tape which supports Light Emitting Diodes or high intensity micro lamps, solar cells and retroreflecting elements. The light emitting diodes may be focused and grouped in pairs for better visibility. The road-marking tape balances the solar energy captured by its solar cells with the emitted light employed to signal or worn motorist.
U.S. Pat. No. 5,425,595 issued to Roper sets forth a POP-UP TRAFFIC CONTROL DEVICE which is supported within a roadway or pavement surface and which includes apparatus for extending the control device above the surrounding pavement surface or withdrawing the device to a generally flush position. The device includes a movable carrier within a housing supported by a lead screw and follower. The rotation of the lead screw provides vertical movement of the pop-up device.
U.S. Pat. No. 5,450,300 issued to Rector, Jr. sets forth a LIGHTING DEVICE for providing light along a runway or taxiway at an airport. A base receptacle is adapted to be positioned along the runway and defines an open end. A sleeve member is movably received within the base receptacle and a replaceable light fixture and connecting apparatus is supported within the sleeve member. The movement of the sleeve member provides corresponding vertical movement of the light apparatus.
U.S. Pat. No. 5,453,663 issued to Nakayama sets forth a LIGHTING APPARATUS WITH AUTO-RECHARGING having a secondary battery, at least two light emitters connected in parallel, and first and second switches. When the first switches are on and the second switches are off, the light emitters are connected in parallel with each other and in series with the secondary battery. When the first switches are off and the second switches are on, the light emitters and secondary battery are connected in series.
U.S. Pat. No. 5,669,691 issued to Barrow sets forth an AIRPORT RUNWAY OR TAXIWAY LIGHT FIXTURE fabricated for flush mounting within the runway or taxiway pavement. An optical prism is detachably mounted in a cavity formed in the device cover and beneath the windows of the device. The prism has three sides forming an equilateral triangle with two of the sides sloping upwardly to an upper edge. A special sealing member fits over the prism and preferably covers one of the two sides which slope upwardly. This member extends about a lower portion of the prism and forms a water tight seal. An electric light is mounted in a bottom receptacle which supports the cover and window. A light channel is formed in the top of the cover and extends from each window towards an edge of the cover.
U.S. Pat. No. 5,839,816 issued to Varga et al. sets forth a ROAD MARKER for use either flush with or preferably slightly below the surface of a road. The road marker includes recharging batteries which are solar operated together with light emitting diodes. During darker night conditions, the solar batteries provide energy sources for the light emitting diodes.
U.S. Pat. No. 5,984,570 issued to Parashar sets forth a SELF ENERGIZED AUTOMATIC SURFACE MARKER having a housing and filler to support and protect a solar powered energy storage system. The circuitry draws power from the solar cells and stores energy in a plurality of storage capacitors. When ambient light dims, the circuitry operates a timing device which causes one or more light emitting diodes to blink and provide directed light toward approaching traffic. The top of the housing protects the solar cell while facilitating its reception of solar energy. The duty cycle may be adjusted to levels consistent with sunlight and operating time.
British Patent 965,583 issued to Greenhalgh sets forth IMPROVEMENTS IN REFLECTOR DEVICES FOR ROADWAYS OR LIKE SURFACES. a similar British Patent 1,018,831 also issued to Greenhalgh sets forth IMPROVEMENTS IN REFLECTOR DEVICES FOR ROADWAYS both of which utilize similar generally cylindrical housings received within appropriate recesses formed in roadway surfaces. The housings further support an upwardly extending member which includes one or more reflectors.
European Patent Application EP0323682A1 sets forth MODULAR FLOOR COVERING UNITS WITH BUILT IN LIGHTING used for guiding the occupants of a building along a path of travel within the building. The modular floor comprises carpet tiles which are supported in abutting arrangement to cover the structure floor. Some of the tiles include signal units having a light transmissive molded plastic housing positioned within an opening formed in the tiles. Light emitting diodes are supported within the housing and are energized by an electrical cable to provide a visually discernible pathway on the floor.
European Patent Application EP0562702A1 sets forth lighting elements which form a geometric structure within a floor surface.
European Patent Application EP0658655A1 sets forth an illumination device having at least one light emitting diode partially embedded in a solid translucent material. The translucent material includes particles which are capable of deffracting light and a cohesive element. The device may be used in road marking or similar environments.
While the foregoing described prior art devices have in varying extents improved the art and have in some instances enjoyed commercial success, there remains nonetheless a continuing need in the art for ever more effect, reliable and improved lighting strips for direction and guidance systems.
Accordingly, it is a general object of the present invention to provide an improved light strip for direction and guidance systems. It is a more particular object of the present invention to provide an improved lighting strip for direction and guidance systems which may be flush mounted within pavement areas of vehicular traffic such as roadways, airport runways and taxiways, and areas of pedestrian foot traffic. It is a further object of the present invention to provide an improved lighting strip for direction and guidance systems which is integrally strong enough to support the wear and impact of vehicle traffic thereacross or thereupon as well as foot traffic of pedestrians.
In accordance with the present invention there is provided a lighting strip for direction and guidance systems, the lighting strip comprising: an elongated base formed of an insulating material and defining first and second ends, opposed sides and an upper surface; at least one elongated strip supported upon the upper surface; a first plurality of light emitting diodes supported on the at least one elongated strip; means for energizing the light emitting diodes supported at the first end; a top cover formed of a light transmissive material encapsulating the upper surface, the elongated strip and the first plurality of light emitting diodes; and a light reflective surface formed on the upper surface, the light emitting diodes producing visible light some of which travels outwardly through the top cover after being reflected from the light reflective surface.